Network Working Group A. Ryan Internet-Draft Limelight Networks Updates: 8006, 8008 (if approved) B. Rosenblum Intended status: Standards Track Vecima Expires: 25 April 2022 N. Sopher Qwilt 22 October 2021 CDNI Capacity Insights Capability Advertisment Extensions draft-ryan-cdni-capacity-insights-extensions-01 Abstract Open Caching architecture is a use case of Content Delivery Networks Interconnection (CDNI) in which the commercial Content Delivery Network (CDN) is the upstream CDN (uCDN) and the ISP caching layer serves as the downstream CDN (dCDN). This document supplements to the CDNI Capability Objects defined in RFC 8008 and CDNI Metadata Objects in RFC 8006. The defined Capability Objects structure and interface for advertisments and managment of a downstream CDN capacity. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on 25 April 2022. Copyright Notice Copyright (c) 2021 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Ryan, et al. Expires 25 April 2022 [Page 1] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Requirements Language . . . . . . . . . . . . . . . . . . 4 1.3. Objectives . . . . . . . . . . . . . . . . . . . . . . . 4 2. CDNI Additonal Capability Objects . . . . . . . . . . . . . . 5 2.1. Telemetry Capability Object . . . . . . . . . . . . . . . 5 2.1.1. Telemetry Source Object . . . . . . . . . . . . . . . 6 2.1.1.1. Telemetry Source Types . . . . . . . . . . . . . 7 2.1.1.2. Telemetry Source Metric Object . . . . . . . . . 7 2.1.2. Telemetry Capability Object Serialization . . . . . . 8 2.2. CapacityLimits Capability Object . . . . . . . . . . . . 9 2.2.1. Capacity Limit Object . . . . . . . . . . . . . . . . 10 2.2.1.1. Capacity Limit Types . . . . . . . . . . . . . . 11 2.2.1.2. Capacity Limit Telemetry Source Object . . . . . 11 2.2.2. Capacity Limit Object Serialization . . . . . . . . . 12 2.3. RequestedCapacityLimits Object . . . . . . . . . . . . . 13 2.3.1. Requsted Limits Object . . . . . . . . . . . . . . . 14 2.3.2. Telemetry Capability Object Serialization . . . . . . 14 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 3.1. CDNI Payload Types . . . . . . . . . . . . . . . . . . . 15 3.1.1. CDNI FCI Telemetry Payload Type . . . . . . . . . . . 16 3.1.2. CDNI FCI Capacity Limits Payload Type . . . . . . . . 16 3.1.3. CDNI MI Requested Capacity Limits Payload Type . . . 16 4. Security Considerations . . . . . . . . . . . . . . . . . . . 17 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 17 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 6.1. Normative References . . . . . . . . . . . . . . . . . . 17 6.2. Informative References . . . . . . . . . . . . . . . . . 17 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 1. Introduction The Streaming Video Alliance [SVA] is a global association that works to solve streaming video challenges in an effort to improve end-user experience and adoption. The Open Caching Working Group [OCWG] of the Streaming Video Alliance [SVA] is focused on the delegation of video delivery requests from commerical CDNs to a caching layer at the ISP's network. Open Caching architecture is a specific use case of CDNI where the commercial CDN is the upstream CDN (uCDN) and the ISP caching layer is the downstream CDN (dCDN). While delegating Ryan, et al. Expires 25 April 2022 [Page 2] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 traffic from one CDN to the other, it is important to make sure that an appropriate amount of traffic is delegated. In order to achive that, the SVA Open Caching Capacity Insight Specification [OC-CII] defines a feedback mechanism to inform the delegator how much traffic is appropriate to delegate. The traffic level information provided by that interface will be consumed by entities, such as the Open Caching Request router [OC-RR], to help inform that entity's traffic delegation decisions. This document defines and registers CDNI Payload Types (as defined at section 7.1 of [RFC8006]). These Payload types are used for Capability Objects added to those defined at section 4 of [RFC8008], which are required for the Open Caching Capacity Insights Interface [OC-CII]. For consistency with other CDNI documents this document follows the CDNI convention of uCDN (upstream CDN) and dCDN (downstream CDN) to represent the commercial CDN and ISP caching layer respectively. This document registers two CDNI Payload Types (section 7.1 of [RFC8006]) for the defined capability objects: * Telemetry Payload Type: A payload type for the capability object which defines the supported telemetry sources, the metrics made available by that source, and corresponding configuration appropriate to the type of the source (host, port, protocol, etc..) * CapacityLimits Payload Type: a payload type for the capability object which defines Capacity Limits based on a set of defined limit types and a mapping from those limits to corresponding telemetry sources for supporting real-time metrics. and describes usage of a CDNI Generic Metadata object: * MI.RequestedCapacityLimits: A generic CDNI Metadata object which allows the uCDN to solicit the dCDN to reconsider Limits. This object is being proposed as part of CDNI Metadata Model Extensions [OC-MME] 1.1. Terminology The following terms are used throughout this document: * CDN - Content Delivery Network Additionally, this document reuses the terminology defined in [RFC6707], [RFC7336], [RFC8006], [RFC8007], [RFC8008], and [RFC8804]. Specifically, we use the following CDNI acronyms: Ryan, et al. Expires 25 April 2022 [Page 3] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 * uCDN, dCDN - Upstream CDN and Downstream CDN respectively (see [RFC7336] ) 1.2. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 1.3. Objectives In order to enable information exchange between a uCDN and a dCDN about acceptable levels of traffic to delegate, a design has been developed as follows: In normal operation a uCDN will communicate with a dCDN, via an interface, to collect and understand any limits that a dCDN has set forth for traffic delegation from a uCDN. These limits will come in the form of metrics such as bits per second, requests per second, etc.. These limits can be thought of as Not to Exceed (NTE) limits. The dCDN should provide access to a telemetry source of near real time metrics that the uCDN can use to track current usage and compare that to the limits the dCDN has put forth and adjust traffic delegation decisions accordingly to keep current usage under the specified limits. In summary, the dCDN will inform the uCDN of limits in how much traffic it should delegate towards the dCDN and then provide a telemetry source that the uCDN can use to track its current usage. This allows for a non ambiguous definition of what a particular limit means and how to track usage against it. Limits that are communicated from the dCDN to the uCDN should be considered valid based on the TTL of the response. The intention is that the limits would be long lived and would represent a reasonable peak limit that the uCDN should target throughout the course of a time period defined by the TTL. In the event that a dCDN needs to inform a uCDN of an update to a previously communicated limit, the dCDN will be able to leverage a uCDN callback endpoint to inform the uCDN of adjusted limits. The most common use case for this would be related to dCDN infrastructure issues which reduced the amount of capacity available. In the inverse of the above, if a uCDN would like to ask a dCDN to reconsider a previously established limit, the uCDN can make a call to the dCDN API interface with a proposed limit. The dCDN can Ryan, et al. Expires 25 April 2022 [Page 4] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 consider the requested limit and choose to send the uCDN an updated limit if it meets the dCDN criteria. This is an asynchronous process. When the uCDN sends the solicitation to the dCDN, the dCDN will acknowledge receipt of the request, but will process the request with no guarantee that it will trigger an update to any limits. 2. CDNI Additonal Capability Objects Section 5 of [RFC8008] describes the FCI Capability Advertisement Object, which contains a CDNI Capability Object as well as the capability object type (a CDNI Paylod Type). The section also defines the Capability Objects per such type. Below we define two additional Capability Objects. Note: In the following sections, the term "mandatory-to-specify" is used to convey which properties MUST be included when serializing a given capability object. When mandatory-to-specify is defined as "Yes" for an individual property, it means that if the object containing that property is included in an FCI message, then the mandatory-to-specify property MUST also be included. 2.1. Telemetry Capability Object The Telemetry Capability Object is used to define a list of telemetry sources made available by the dCDN to the uCDN. Telemetry data is being defined as near real time aggregated metics of dCDN utilization, such as bits per second egress, and should be specific to the uCDN and dCDN traffic delegation relationship. Telemetry data is uniqiely defined by a source id, a metrics name, along with the footprints that are associated with an FCI.Capability advertisement. Telemetry data is an important component for CDNI delegation. The reasons that Telemetry information is important to traffic delegation is as follows: In situations where there are mutiple delegations, a uCDN will need to incorporate usage information from it's dCDN in such as manner as to allow higher level uCDNs to gain vislibility into traffic that is being delegated to a dCDN. An example of this is if a Content Provider delegates traffic directly to a CDN, and that CDN decides to further delegate traffic to a dCDN, if the Content Provider polls the uCDN for traffic usage, without the uCDN integrating the Telemetry data of it's dCDN, any traffic the uCDN delegated would become invisible to the Content Provider. When defining a Capacity Limit, the meaning of a limit might be considered ambiguous if the uCDN and dCDN are defining current usage via different data sources. Having the dCDN provide a data source defining usage that both itself and the uCDN reference, allows a non ambiguous metric to use when determing current usage and how that compares to a limit Ryan, et al. Expires 25 April 2022 [Page 5] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Property: sources Description: Telemetry sources made available to the uCDN. Type: A JSON array of Telemetry Source objects (see Section 2.1.1). Mandatory-to-Specify: Yes. 2.1.1. Telemetry Source Object The Telemetry Source Object is built of an associated type, a list of exposed metrics, and type-specific configuration data. Property: id Description: A unique identifier of a telemetry source. Type: String. Mandatory-to-Specify: Yes. Property: type Description: A valid telemetry source type. See Section 2.1.1.1. Type: String. Mandatory-to-Specify: Yes. Property: metrics Description: The metrics exposed by this source. Type: A JSON array of Telemetry Source Metric objects (see Section 2.1.1.2). Mandatory-to-Specify: Yes. Property: configuration Ryan, et al. Expires 25 April 2022 [Page 6] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Description: a source-specific representation of the Telemetry source configuration. For the generic source type, this configuration format is defined out-of-band. For other types, the configuration format will be specified in a yet to be defined Telemetry Interface specification. The goal of this element is to allow for forward compatability with a formal Telemetry interface. Type: A JSON object: TBD Mandatory-to-Specify: No. 2.1.1.1. Telemetry Source Types Below are the listed valid telemetry source types. At the time of this draft, the type registry is limit to a single type of Generic. The intention of this type registry is to allow for future extension to reference a yet to be drafted specification for a CDNI Telemetry interface, which would standardize the definition, format,etc of Telemetry data between participants of a CDNI workflow. +=============+======================================+ | Source Type | Description | +=============+======================================+ | generic | An object which allows for | | | advertisement of generic datasources | +-------------+--------------------------------------+ Table 1 2.1.1.2. Telemetry Source Metric Object The Telemetry Source Metric Object describe the metric to be exposed. Property: name Description: An identifier unique within this telemetry source. Type: String. Mandatory-to-Specify: Yes. Property: time-granularity Description: Represents the time frame that the data represents in seconds. I.e. is this a data set over 5 minutes, one hour, etc.. Ryan, et al. Expires 25 April 2022 [Page 7] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Type: Integer. Mandatory-to-Specify: No. Property: data-percentile Description: The percentile calculation the data represents, i.e. 50 percentile would equate to the median over the time- granularity. Lack of a data-percentile will mean that the data is the average over the time representation. Type: Integer. Mandatory-to-Specify: No. Property: latency Description: Time in seconds that the data is behind of real time. This is important to specify to help the uCDN to understand how long it might take to reflect traffic adjustments in the metrics. Type: Integer. Mandatory-to-Specify: No. 2.1.2. Telemetry Capability Object Serialization The following shows an example of Telemetry Capability including 2 metrics for a source, that is scoped to a footprint. Ryan, et al. Expires 25 April 2022 [Page 8] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 "capabilities": [ { "capability-type": "FCI.Telemetry", "capability-value": { "sources": [ { "id": "capacity_metrics_region1", "type": "generic", "metrics": [ { "name": "egress_5m", "time-granularity": 300, "data-percentile": 50, "latency": 1500 }, { "name": "requests_5m", ... } ] } ] }, "footprints": [ ] } ] 2.2. CapacityLimits Capability Object The Capacity Limits Capability Object enables the dCDN to specify traffic delegation limits to a uCDN within an FCI.Capabilities advertisement. The limits specified by the dCDN will inform the uCDN on how much traffic can be delegated to the dCDN. The limits specified by the dCDN should be considered Not To Exceed (NTE) limits. The limits should be based on near time telemetry data that the dCDN provides to the uCDN. In any instance where there are multiple limits, the uCDN must consider and honor all specified limits and use the most restrictive limit when applicable. Property: total-limits Description: The top level limits for the footprint. This limit represents traffic limits scoped to total delegation from the uCDN towards the dCDN. Ryan, et al. Expires 25 April 2022 [Page 9] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Type: A JSON array of Capacity Limit objects (see Section 2.2.1). Mandatory-to-Specify: Yes. Property: host-limits Description: Limits for particular CDN Domains. These limits are more specific than the total-limits values since they are scoped to a particual host value. Type: A JSON array of Capacity Limit objects (see Section 2.2.1). Mandatory-to-Specify: No. 2.2.1. Capacity Limit Object The Capacity Limit Object is a JSON object which will be used with the total-limits and host-limits objects. Property: limit-type Description: The units of maximum-hard and maximum-soft. Type: String. One of the values listed in Section 2.2.1.1. Mandatory-to-Specify: Yes. Property: maximum-hard Description: The maximum unit of capacity that is available for use. Type: Integer. Mandatory-to-Specify: Yes. Property: maximum-soft Description: A soft limit at which an upstream should consider deducing traffic to prevent hitting the hard limit. Type: Integer. Mandatory-to-Specify: No. Property: telemetry-source Ryan, et al. Expires 25 April 2022 [Page 10] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Description: Mapping of each a particular limit to a specific metric with relevant real-time data provided by a telemetry source. Type: Capcity Limit Telemetry Source object (see Section 2.2.1.2). Mandatory-to-Specify: No. Property: host Description: The CDN Domain to which the limit applies. Type: String. Mandatory-to-Specify: Only when included within a host-limits array. 2.2.1.1. Capacity Limit Types Below are listed the valid capacity limit types. Additional limits would need to be specified and extended into this list. The values specified here represent the types that were identified as being the most relevant metrics for the purposes of traffic delegation between CDNs. +=================+=====================+ | Limit Type | Units | +=================+=====================+ | egress | Bits per second | +-----------------+---------------------+ | requests | Requests per second | +-----------------+---------------------+ | storage-size | Total bytes | +-----------------+---------------------+ | storage-objects | Count | +-----------------+---------------------+ | sessions | Count | +-----------------+---------------------+ | cache-size | Total bytes | +-----------------+---------------------+ Table 2 2.2.1.2. Capacity Limit Telemetry Source Object The Capacity Limit Telemetry Source Object refers to a specific metric within a Telementry Source. Ryan, et al. Expires 25 April 2022 [Page 11] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Property: id Description: Reference to the "id" of a telemetry source defined by a Telemetry Capability object. Type: String. Mandatory-to-Specify: Yes. Property: metric Description: Reference to the "name" property of a metric defined within a telemetry source of an FCI.Telemetry Capability object. Type: String. Mandatory-to-Specify: Yes. 2.2.2. Capacity Limit Object Serialization The following shows an example of an FCI.CapacityLimits object. "capabilities": [ { "capability-type": "FCI.CapacityLimits" "capability-value": { "total-limits": [ { "limit-type": "egress", "maximum-hard": 50000000000, "maximum-soft": 25000000000, "telemetry-source": { "id": "capacity_metrics_region1", "metric": "egress_5m" } } ], "host-limits": [ { "host": "serviceA.cdn.example.com", "limits": [ "limit-type": "egress", "maximum-hard": 20000000000, "maximum-soft": 10000000000, "telemetry-source": { "id": "capacity_metrics_region1", "metric": "egress_service2_5m" Ryan, et al. Expires 25 April 2022 [Page 12] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 } ] }, { "host": "serviceB.cdn.example.com", "limits": [ "limit-type": "egress", "maximum-hard": 30000000000, "maximum-soft": 15000000000, "telemetry-source": { "id": "capacity_metrics_region1", "metric": "egress_service2_5m" } ] } ] }, "footprints": [ ] } ] 2.3. RequestedCapacityLimits Object The MI.RequestedCapacityLimits Generic Metadata object, which is cross referenced in CDNI Metadata Model Extensions [OC-MME], is fully detailed within this document. To enable the uCDN to request changes in dCDN limits, a new metadata object is introduced. Using this object, a uCDN can request that a dCDN reconsider limits, as defined by an FCI.CapacityLimits advertisement. The MI.RequestedCapacityLimits object must be scoped within an MI.HostIndex object and as such must be scoped to a host. The host parameter value must be a CDN-Domain that the dCDN has been configured to accept requests for. It is the responsibility of the dCDN to make any required adjustments to the FCI.CapacityLimits.total-limits if any per host limit updates might exceed values specified via the FCI.CapacityLimits.total-limit. The requested limits must specify a footprint, and that footprint should be one in which the dCDN has advertised a capability to support. Property: requested-limits Description: Capacity Limits being requedted by the uCDN to the dCDN. Ryan, et al. Expires 25 April 2022 [Page 13] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Type: A JSON array of Requested Limits objects (see Section 2.3.1). Mandatory-to-Specify: Yes. 2.3.1. Requsted Limits Object The Requested Limit Object is build of an associated type, a value assocaited with the type, and the footprints that the limit should be associated with. Property: limit-type Description: A limit type as defined in Section 2.2.1.1. Type: String. Mandatory-to-Specify: Yes. Property: limit-value Description: A unit of capacity defined in the maximum-hard property of Section 2.2.1. Type: Integer. Mandatory-to-Specify: Yes. Property: footprints Description: The CDNI Footprint objects this requested limit are associated with. Type: A JSON array of CDNI Footprints (see [RFC8006]). Mandatory-to-Specify: Yes. 2.3.2. Telemetry Capability Object Serialization The following shows an example of MI.RequestedCapacityLimits object. Ryan, et al. Expires 25 April 2022 [Page 14] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 { "host": "serviceA.cdn.example.com", "host-metadata": { "metadata": [ ..., { "generic-metadata-type": "MI.RequestedCapacityLimits", "generic-metadata-value": { "requested-limits": [ { "limit-type": "egress", "limit-value": 80000000000, "footprints": [{ "footprint-type": "ipv4cidr", "footprint-value": ["192.0.2.0/24", "198.51.100.0/24"] }] }, { ... } ] } } ] } } 3. IANA Considerations 3.1. CDNI Payload Types simialr to the type definitions described in section 7.1 of [RFC8006] as well as the types described in section 6.1 of [RFC8008]. This document requests the registration of the three additional payload types: Ryan, et al. Expires 25 April 2022 [Page 15] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 +============================+===============+ | Payload Type | Specification | +============================+===============+ | FCI.Telemetry | RFCthis | +----------------------------+---------------+ | FCI.CapacityLimits | RFCthis | +----------------------------+---------------+ | MI.RequestedCapacityLimits | RFCthis | +----------------------------+---------------+ Table 3 [RFC Editor: Please replace RFCthis with the published RFC number for this document.] 3.1.1. CDNI FCI Telemetry Payload Type Purpose: The purpose of this Payload Type is to list the supported telemetry sources and the metrics made available by each source). Interface: FCI. Encoding: See section Section 2.1. 3.1.2. CDNI FCI Capacity Limits Payload Type Purpose: The purpose of this Payload Type is to define Capacity Limits based on a utilization metrics corresponding to telemetry sources provided by the dCDN. Interface: FCI. Encoding: See section Section 2.2. 3.1.3. CDNI MI Requested Capacity Limits Payload Type Purpose: The purpose of this Payload Type is to allow a uCDN to request a CapacityLimit update from a dCDN Interface: MI. Encoding: See section Section 2.3. Ryan, et al. Expires 25 April 2022 [Page 16] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 4. Security Considerations This specification is in accordance with the CDNI Request Routing: Footprint and Capabilities Semantics. As such, it is subject to the security and privacy considerations as defined in Section 8 of [RFC8006] and in Section 7 of [RFC8008] respectively. 5. Acknowledgements The authors would like to express their gratitude to TBD for TBD (their guidance / contribution / reviews ...) 6. References 6.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC8006] Niven-Jenkins, B., Murray, R., Caulfield, M., and K. Ma, "Content Delivery Network Interconnection (CDNI) Metadata", RFC 8006, DOI 10.17487/RFC8006, December 2016, . [RFC8007] Murray, R. and B. Niven-Jenkins, "Content Delivery Network Interconnection (CDNI) Control Interface / Triggers", RFC 8007, DOI 10.17487/RFC8007, December 2016, . [RFC8008] Seedorf, J., Peterson, J., Previdi, S., van Brandenburg, R., and K. Ma, "Content Delivery Network Interconnection (CDNI) Request Routing: Footprint and Capabilities Semantics", RFC 8008, DOI 10.17487/RFC8008, December 2016, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8804] Finkelman, O. and S. Mishra, "Content Delivery Network Interconnection (CDNI) Request Routing Extensions", RFC 8804, DOI 10.17487/RFC8804, September 2020, . 6.2. Informative References Ryan, et al. Expires 25 April 2022 [Page 17] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 [OC-CII] Ryan, A., Ed., Rosenblum, B., Goldstein, G., Roskin, R., and G. Bichot, "Open Caching Capacity Insights - Functional Specification (Placeholder before publication)", . [OC-MME] Goldstein, G., Ed., Power, W., Bichot, G., and A. Siloniz, "CDNI Metadata Model Extensions", Version 00, 3 January 2022, . [OC-RR] Finkelman, O., Ed., Hofmann, J., Klein, E., Mishra, S., Ma, K., Sahar, D., and B. Zurat, "Open Caching Request Routing - Functional Specification", Version 1.1, 4 October 2019, . [OCWG] "Open Caching Home Page", . [RFC6707] Niven-Jenkins, B., Le Faucheur, F., and N. Bitar, "Content Distribution Network Interconnection (CDNI) Problem Statement", RFC 6707, DOI 10.17487/RFC6707, September 2012, . [RFC7336] Peterson, L., Davie, B., and R. van Brandenburg, Ed., "Framework for Content Distribution Network Interconnection (CDNI)", RFC 7336, DOI 10.17487/RFC7336, August 2014, . [SVA] "Streaming Video Alliance Home Page", . Authors' Addresses Andrew Ryan Limelight Networks 1465 N Scottsdale Road, Suite 500 Scottsdale , AZ 85257 United States of America Email: andrew@andrewnryan.com Ryan, et al. Expires 25 April 2022 [Page 18] Internet-Draft CDNI Capacity Insights Capability Advert October 2021 Ben Rosenblum Vecima 4375 River Green Pkwy #100 Duluth , GA 30096 United States of America Email: ben@rosenblum.dev Nir B. Sopher Qwilt 6, Ha'harash Hod HaSharon 4524079 Israel Email: nir@apache.org Ryan, et al. Expires 25 April 2022 [Page 19]